|
|
Applications of spectrally and spatially resolved NMR: induced anisotropy and phase transition in hydrogels; new relaxation probes for imaging
Bernášek, Karel ; Lang, Jan (advisor) ; Hanyková, Lenka (referee) ; Janisova, Larysa (referee)
Nuclear magnetic resonance is a non-invasive way to observe material properties on a molecular level. Magnetic resonance imaging is an important diagnostic tool in medicine. Molecules of several metabolites in muscle tissue show similar interactions as molecules partially oriented in orienting media. These interactions could provide new information about processes in vivo, this can serve for diagnostics of metabolism. New insight into the function is gained by observation of metabolites in orienting media. Observable anisotropic interactions in muscle tissue in vivo could be used for diagnostic purposes. Anisotropic NMR interaction of solvent as a new method for observation of phase transition of hydrogel with temperature change or change of solvent composition. Use of magnetic resonance imaging in slices to observe the collapse of polyacrylamide in water-acetone mixtures. Use of diffusion-weighted magnetic resonance imaging to observe phase transition of PNIPAM-based semi-interpenetrating polymer.
|
|
|
Characterization of Novel Gd-DOTA Related Contrast Agents for Magnetic Resonance Imaging (MRI)
Rosenkrancová, Anna ; Šoltésová, Mária (advisor) ; Hanyková, Lenka (referee)
This work focuses on the characterization of a new potential contrast agent con- sisting of β-cyclodextrin and 1,4,7,10-tetraazacyylododecan-4,7,10-triocta-1-methyl[(4- aminophenyl)methyl]phosphinoic acid, short for DO3APABn . Using 2D NMR experi- ments, the hydrogen and carbon spectrum signals of both molecules were assigned. There was a temperature dependency studied in DO3APABn . By evaluating 13 C relaxation, re- laxation times T1, T2 and Nuclear Overhauser effect were determined. Using the isotropic reorientation model, the rotational correlation time was numerically calculated from the measured values of T1. From the rotational correlation time, the most rigid part of the molecule was found to be the cycle (τc = 264-308 ps). The most mobile is the aromatic methyl phosphine arm, whose correlation time is about half that of the cycle (139-156 ps). 1
|
|
|
Study of temperature-induced phase separation in copolymer solutions
Šťastná, Julie ; Hanyková, Lenka (advisor)
Title: Study of temperature-induced phase separation in copolymer solutions Author: Julie Brüllová Department: Department of Macromolecular Physics Supervisor: RNDr.Lenka Hanyková, Dr. Supervisor's e-mail address: hanykova@kmf.troja.mff.cuni.cz Abstract: The temperature-induced phase transition of poly(acrylamide/N-isopropylmethacryl- amide) random copolymers in D2O solutions and in mixtures of D2O/ethanol and D2O/aceton is studied in this work. This phenomenon is on the molecular level analogous with a phase transition (collapse) in hydrogels. Nuclear magnetic resonance (NMR) spectroscopy was used for the study. Results showed that with increasing content of acrylamide in the copolymer the transition tempe- rature is shifted to higher values, the transition is more gradual and smaller fraction of copolymer is phase separated. The same behaviour was found for higher content of ethanol or acetone in the solvent. If this content and the content of acrylamide is very high, the phase transition in dependence on the composition of solvent appears. The relaxation experiments showed that after the phase separation a part of solvent molecules remains bound to globular structures and its mobility is rescticted. Keywords: temperature induced phase separation, poly(acrylamide/N-isopropylmethacrylamide) random...
|
|
|
Study of temperature-induced phase separation in copolymer solutions
Šťastná, Julie ; Hanyková, Lenka (advisor)
Tit lr: Study of tempera! urc-indneed phase M'paNil ion in cnpol VIIKT noli it ions. Author; .Intie IJriilliiva I Jepar! incut; Department of MiUTOinnleeulai1 |']IVM< .- Supervisor: KM )r.l,enka llauvkova. Dr. Hnpervisoi ' - e-mail address- hanykova" l-imf I loja.mil.cnni.r/ Absl ract: I'lif tcinpci.ii ui I'-indnrcd pi MM' 11 HUM! ion oi pi)ly(;KT\/ A -iiMipropvlnirt h.u-i \- nniiilc) r;nidnru n>|]o|vnici - in [>_>(> snlui ion^ and in mixl mv^ of Dj<) 'd h.iuul ;ind DjO 'acftnn i^ it tidiI'd in linn work. I In.-, plir-immciHMi i.-> on [ lie nmicciihn1 level ;ni;ilof.',nu^ w i t ii ;i phiisc transit ion (coll,-i|ivcl in hydi o;.',cls. Nuclear ina^iiciic rcsnn.imc [ N M I ' ) ->pret n>^e',ip\ v.'a- u-cd tm' the ~lnd>". liesull.h sho\ved thill w i t h nici'i'.i^i nj1, c< ml ent of acrylaiuide in t lie ci >poi\niei1 i he i ra nation r<iinpc- laMii'e i> shifted lo hijdici1 \".ihic-~. t h e 11 aiisit ii ni is iimcc 1^1 adiial ;nid sinallei1 fi'ai I inn of copulx'Uiei is pluihf se|>ai'a!ed. The same liehavionr \\-as fniind ior hiidn-i enntenl i if ct lianol or aeetnne in 1 he Mtlvent. If This emiteiit and t h e content ut" arrylaiuidi' is very ln,",li. the pliaM.' transition in dc pci i delice on the eompo-it ion of snh-cnl appejir- The relnxat ion cxpciinient- sh(J\\-cd ( ha! alter ihe |)hase -eparntion a p;nt...
|
|
|
Spectroscopic Study of the Dynamical Behavior and Interactions in Supramolecular and Macromolecular Systems
Radecki, Marek ; Hanyková, Lenka (advisor)
Title: Spectroscopic Study of the Dynamical Behavior and Interactions in Supramolecular and Macromolecular Systems Author: Marek Radecki Department: Department of Macromolecular Physics Supervisor: Doc. RNDr. Lenka Hanyková, Dr., Department of Macromolecular Physics Abstract: In this thesis, the temperature-induced phase transition in liner polymer solutins and hydrogels of semi-interpenetrating (SIPNs) and interpenetrating (IPNs) polymer networks was studied with respect to various composition, network architecture and procedure. Thermoresponsive linear polymers based on poly(vinyl methyl ether) (PVME) in water and with terc-buthyl based additives, IPNs of polyacrylamide (PAAm), poly(N -isopropylacrylamide) (PNIPAm), poly(N - vinylcaprolactam) (PVCL) and IPNs and SIPNs of poly(N,N -diethylacrylamide) (PDEAAm) were investigated by the methods of nuclear magnetic resonance spectroscopy (NMR), differential scanning calorimetry (DSC), optical microscopy (OM) and swelling experiments. The effect of polymer concentration and presence of additives on the dynamics during the phase separation as well as interactions between the water and the polymer in aqueous solutions of PVME and PVME/additives were established. The increasing content of hydrophilic PAAm component in SIPNs and IPNs shifts the transition toward...
|
|
| |
|
|
Study of temperature-induced phase separation in copolymer solutions
Brüllová, Julie ; Hanyková, Lenka (advisor) ; Starovoytova, Larisa (referee)
Title: Study of temperature-induced phase separation in copolymer solutions Author: Julie Brüllová Department: Department of Macromolecular Physics Supervisor: RNDr.Lenka Hanyková, Dr. Supervisor's e-mail address: hanykova@kmf.troja.mff.cuni.cz Abstract: The temperature-induced phase transition of poly(acrylamide/N-isopropylmethacryl- amide) random copolymers in D2O solutions and in mixtures of D2O/ethanol and D2O/aceton is studied in this work. This phenomenon is on the molecular level analogous with a phase transition (collapse) in hydrogels. Nuclear magnetic resonance (NMR) spectroscopy was used for the study. Results showed that with increasing content of acrylamide in the copolymer the transition tempe- rature is shifted to higher values, the transition is more gradual and smaller fraction of copolymer is phase separated. The same behaviour was found for higher content of ethanol or acetone in the solvent. If this content and the content of acrylamide is very high, the phase transition in dependence on the composition of solvent appears. The relaxation experiments showed that after the phase separation a part of solvent molecules remains bound to globular structures and its mobility is rescticted. Keywords: temperature induced phase separation, poly(acrylamide/N-isopropylmethacrylamide) random...
|
|
|
Spectroscopic Study of the Dynamical Behavior and Interactions in Supramolecular and Macromolecular Systems
Radecki, Marek ; Hanyková, Lenka (advisor)
Title: Spectroscopic Study of the Dynamical Behavior and Interactions in Supramolecular and Macromolecular Systems Author: Marek Radecki Department: Department of Macromolecular Physics Supervisor: Doc. RNDr. Lenka Hanyková, Dr., Department of Macromolecular Physics Abstract: In this thesis, the temperature-induced phase transition in liner polymer solutins and hydrogels of semi-interpenetrating (SIPNs) and interpenetrating (IPNs) polymer networks was studied with respect to various composition, network architecture and procedure. Thermoresponsive linear polymers based on poly(vinyl methyl ether) (PVME) in water and with terc-buthyl based additives, IPNs of polyacrylamide (PAAm), poly(N -isopropylacrylamide) (PNIPAm), poly(N - vinylcaprolactam) (PVCL) and IPNs and SIPNs of poly(N,N -diethylacrylamide) (PDEAAm) were investigated by the methods of nuclear magnetic resonance spectroscopy (NMR), differential scanning calorimetry (DSC), optical microscopy (OM) and swelling experiments. The effect of polymer concentration and presence of additives on the dynamics during the phase separation as well as interactions between the water and the polymer in aqueous solutions of PVME and PVME/additives were established. The increasing content of hydrophilic PAAm component in SIPNs and IPNs shifts the transition toward...
|
|
|
Spectroscopic Study of the Dynamical Behavior and Interactions in Supramolecular and Macromolecular Systems
Radecki, Marek ; Hanyková, Lenka (advisor) ; Matějka, Libor (referee) ; Kronek, Juraj (referee)
Title: Spectroscopic Study of the Dynamical Behavior and Interactions in Supramolecular and Macromolecular Systems Author: Marek Radecki Department: Department of Macromolecular Physics Supervisor: Doc. RNDr. Lenka Hanyková, Dr., Department of Macromolecular Physics Abstract: In this thesis, the temperature-induced phase transition in liner polymer solutins and hydrogels of semi-interpenetrating (SIPNs) and interpenetrating (IPNs) polymer networks was studied with respect to various composition, network architecture and procedure. Thermoresponsive linear polymers based on poly(vinyl methyl ether) (PVME) in water and with terc-buthyl based additives, IPNs of polyacrylamide (PAAm), poly(N -isopropylacrylamide) (PNIPAm), poly(N - vinylcaprolactam) (PVCL) and IPNs and SIPNs of poly(N,N -diethylacrylamide) (PDEAAm) were investigated by the methods of nuclear magnetic resonance spectroscopy (NMR), differential scanning calorimetry (DSC), optical microscopy (OM) and swelling experiments. The effect of polymer concentration and presence of additives on the dynamics during the phase separation as well as interactions between the water and the polymer in aqueous solutions of PVME and PVME/additives were established. The increasing content of hydrophilic PAAm component in SIPNs and IPNs shifts the transition toward...
|
|
|
Melting of a methylated CpG-containing DNA double helix
Bušková, Hana ; Římal, Václav (advisor) ; Hanyková, Lenka (referee)
The melting of a DNA double helix into two single strands is a crucial process for life on Earth. Previous experimental data on the self-complementary sequence CTTm5 CGAAG containing 5-methylcytosine suggests that the melting of an oligonucleotide might be a three-state, rather than two-state process. To assess this, 1 H NMR spectra were measured at varied concentrations of the oligonucleotide in temperatures between 274 and 366 K. Through analysis of the chemical shifts of aromatic hydrogens undergoing fast chemical exchange, we have determined that the most likely intermediate state between a double helix and a single stranded random coil is a structure consisting of two oligonucleotide molecules rather than a structured single strand.
|
guest ::
